Apparatus for handling flow from wells



Nov. 22, 1949 R. A. wERTs APPARATUS FOR HANDLING FLOW FROM WELLS Filed Nov. l5, 1944 Arroz/WSV Patented Nov. 22,k 1949 :Blielxal #Winmx Beatehalifasassignortof eonenthirdsm Bt Ballfmd fene-thixdzm mamut My inventlormeliateslto fl'lowffnom wellsand is eo-ncezrne'el fifths@ -fedfflto` fdevlices eommomy known fasfrg-as 2separators. 'The invention hasfmoremaiftinuhr notatmessage).

napparatu-s'tfov'tfawchtling .lfemsisveLactiomoffitheesol las tain Lthe'desired.- liquid, lex/el; inthefehamheir.,

.heat f mechanisms; are ySubjetec; sito rapidfmar )and deterioration: and-axe het: satisactexzy be @im @AEM openfandclosed positions. aQther. ewekacqmgxos ,have beenfproposetlaud employedhut se Rmally involvelcomplated; -mehanims .station chamber orYeompliczatedrlnkaeessa exterior V.of the cghamhersafrgldrf@4 :ofteIAl-fslblqtt to. inaccuracies .became vthe valwes--atefqnhal aned and affect theaactionsof; thenloatnfdatphragm or other levelxesponswei-fmeans.

Another; object .of thisinyention ,istopxrxvtde aL separator in which thelevel 4centraal-11er;ets.. the form Qf.a..sing1e sommet.,.unit.,entieet egg,- 'Iternal-,of the .separation chamber. `The; iqgiti level controller of vthe present inventiongagisgtg single unit whiehmay 'be :.:most aduantagwsly .tillscharge lmes butowing tofthefvqrip bag); mpsessur'es fm2-these llines, -'s u'ch 'diaphragm soin.-

trols have-'not*prendi-practical' Qrsucces's In ==zneohanisiln "of -'the -present 1 invention '.'thehe sing-le `-'clialfilgragrn 'acted' 'Qn by" hhas PIQS.- @sure the sepa-rater andby "the, ,hel rspmesstrre actuallypresentin the separationchamg ffbelM-alrdthere areindividual valvesholitrlleby diaphragm -jgoverninggtheiowdf landgas "Mythe isehargellines. They o il valve, isnormlly -iheld jl'osed by the"liquidheadpresure whilegthe y"sasfvalwf is a balanced valvenot slibjeet..t,o pertain :action due .to .variable ,bak,pressuies that mayexisgt mithegasdisohargeline. Bak pressures thejdischarselnes do-notaeet .the atbn Oi'theldiaphnagm.,with,fthefreesnltthat .the 'controller ac'tswth uprecision;to mantai-naasuh arranged .a1-theI exterienof theft-separati@ mak Stall-@UY-uniolm'liguidlevelJmthetsepafratera where it, .isreadily4 accessible Wham-ibis not. subject to the, .wearing and. deteriemtingsae-f tion., .0I the constantly istunhed-uid-witbmthe tank,

Another Yobject, Qf ..this .i inventions-.is to'pmvide a, separator. ofthe dharacter mentioned' iin-gimen a., relativelysmall vise of, the actuaLY-liquidtieyel in the .tank- ,produces `su-hstantiaatl or inamovemeneoff the New@ fthetliquid inaocumtely manipulate AIYQther object.' of'y 'this` 'invention it-stefipmuide aseparaton. ofthe. Character. referredtofimwhish the. normally .Working-.pants .llequines mangimi?- menmmegulationr manual :setting and inl-whim fthexeaare no parts .thatsoanahe tame-md withfl-er -ftoaaitect @penali-im charge aline, thusf reducing,- eetof- @the .liquidflevehcambezmamtainettgiigtisp@ 2,488,841 ,l i f ration chamber and Fig. 3 is an enlarged frag' mentary vertical detailed sectional view illustrating one of the slip joints or adjustable connec- 4 flected downwardly thereby. 'I'he form and disposition of the baiiie 2| are such that the incoming fluid under pressure is fanned out and directed downwardly in the form of a broad stream. It has been found that this fanned out stream of the incoming Huid effectively breaks downlthe foam that otherwise tends to coll'ectlonthesurface of the liquid in the tank ID.

The level controller which is an important feature of the invention is preferably a single compact unit entirely external of the tank I0.

yThe controller operates automatically and precisely in response to the actual liquid head to maintainthe correct relationship between the oil and gas discharge and thus maintain a substantially uniform or stable liquid level in the tions provided between the separation chamber and the level control unit. l

The apparatus of the present invention `may be said to comprise, generally, a separating tank I0 receiving flow from a fluid inlet line I I, a liquid discharge line I2 and a gas discharge line I3, means I4 for handling the flow entering the tank I0 to minimize foam, a level controllercomprising a diaphragm means I5 and liquid and gas discharge valves I6 and I1, respectively, operated byv the diaphragm means I5, and adjusting means I8 for the level controller.

The tank I0 serves to receive the flow, which is amixture of oil and gas, from a well or a group of wells and is a pressure-tight vesselin which the separation of the gases from theliquid occurs. As illustrated, the tank I0 is a vertically disposed elongate vessel supported by a suitable base Ia. The fluid inlet line II carrying the oil and gas to be separated enters the upper portion of the tank I0 at a point preferably well above the liquid level L. The oil discharge line I2 communicates with the lower portion of the tank IIJ at a point spaced between its bottom and the liquid normal or average level L, while the gas discharge line I3 communicates with the upper end portion of the tank. A valve controlled drain line I9 communicates with the lower end of the tank II) to permit the draining awayof solidmatter that settles from the liquid. It is to be observed that the tank I0 is a very simple structure and does not house or require mechanical linkages, internal valves, or the like.

The means I4 utilizes the energy of thefincoming fluid to break up the foam bubbles which tend to form on the liquid surface in the tank I0 as aresult of the gas coming out of solution. The means I4 operates to direct the incoming fluid downwardly against the foam or liquid suri 'face in the tank in such a manner that it breaks the bubbles and thus destroys the foam and increases the separation rate of the separator. The separator being without a oat or any other liquid level control mechanism within the tank I0, it is possible to effectively direct the incoming fluid downwardly by the means I4 to break up the foam without interfering with the proper operation of the separator.

The means I4 includes a tubular portion or A lo tank. `The level controller includes the diaphragm means I5 which is directly acted upon by' thehead pressure of liquid in the tank I0 to move in response to any appreciable change the level of the liquid in the tank.

The diaphragm means I 5 includes a diaphragm casing 2'1 made up of upper and lower sections secured together at their margins by ilange and bolt connections 28. A flexible diaphragm 29 extends through or across the diaphragm chamber 30 and has its marginal portion secured between the flanges of the connection 28. The diaphragm 29 has a central hub 3| which carries diaphragm supporting discs 32. The discs 32 engage with the opposite sides of the diaphragm 29 to give stability to the major central portion of the diaphragm but the discs are proportioned 'to leave a substantial portion of the diaphragm free to ex.

, In accordance with the invention one side of the diaphragm 29 is subjected to the gas pressure existing within the tank I Il and the other side of the diaphragm is subjected to the head pressure of the liquid in the tank plus the gas pressure. A pipe or line 33 extends from the liquid discharge line I2 to the diaphragm means I5 where it communicates with a port 34 formed in the wall of the diaphragm casing 21. The port 34 communicates with the lower portion of the diaphragm chamber 30 so pressure from the line I2 acts on the lower side of the diaphragm. A

similar line 35 communicates with the gas discharge line I3 and extends to the diaphragm means I5 where it communicates with a port 36 which has communication with the upper portion of the diaphragm chamber 30 so pressure in the line I3 which corresponds to the gas pressure inthe tank I0 acts on the upper side of the diaphragm. As illustrated, it is preferred to arrange the diaphragm means I5 adjacent to the tank I0 and in a horizontal plane below the normal or intended liquid level L.

With the structure thus far described it will be seen that the diaphragm 29 is at all times subjected to head pressure from liquid in the tank and to gas pressure corresponding to that in the tank.

- The valves I6 and II control the flow from lines I2- and I3 to discharge lines 60 and 6I, respectively, and are preferably directly connected with the diaphragm means I5 to be directly operated or controlled thereby. In the preferred construction the valve I1 is of the balanced type so that the action of the diaphragm 29 is unaffected by vari-ations in the back pressures in the gas discharge line 6I. The valve I6 may be an ordinary or simple valve arranged between the line I2 and liquid discharge line 60. Valve I6 is installed so that the liquid head pressure northe gas from the separator.

the hub by a`v nut 53.

mauytends ,te nomine-loses. :rheslinesfss and :.35 `connect with -thezlines-:I landzfl, respectively, :so thatthe linesl 33 and :35zare always infree or vZfull communication withethe upper and v=lower portions, respectively, of thetank I 0.

The valve I5; as shownin-'the drawings, includes a valve body 3i lconnected between the lines I2 and 6) by flange andbolt connections 38; A partition 4I is provided Linthe valve body `to separate its upstream and downstream sides.-

The kpartition 14| Vhas an opening through it @equipped Witha seatr43. 'Theseat 43 opensf-or faces .upward or in the 'directionv of the vupstream side of the Valve. A stem 4S enters thevalve `body 3l from its-upper end "and carries-a-valve head 55 which cooperates with the seat .43. The fvalve head has ,projecting guide wingsl 56 -slidably v vfitting the seat. The arrangement -is suchv that f-the valve head-55 moves downward'intoengage- `ment with the V'seat Vand-the head pressure 'of liquid handled by the-valve normally tends to hold vthe valve closed orin'engagement-with theseat.

The v-alve Il is a balanced valve and handles The Valve vI'I inycludes a body 39 connected between the lines I3 andI by langeandbolt connections 46. The body of the valve Vincludes'a partition 42 which carri'esvertically spaced'downwardly faced valve -seatsfliland divides thefinterior of the body so that gas admitted from line I Z'tends to flow down through the uppermostfseat and up through the lowermost seat while gaspassing the seats flows from the space lbetweenthe two seats to the into seating'engagementhwiththe 'seats and seat xsimultaneously. The valve 'heads have projecting guidewings 58''slidab1y"1'itting the seats '44.

VThe construction just referred to and which is `Aclearly illustrated infFig.-21is atypical balanced valve construction iniwhich the pressures exerted by the gas controlled bythe"valve and by the back pressures acting on the Valve` are balanced.

In accordance with the'preferred arrangement the-valves I'6 and I'I are secured'together orare joined with or byfth'e diaphragm-means I5 soithat the twovalves and thefdiaphragm constitutea 50 single, compact unit or pressure control.

The Valves I6 and Ilmay be associated or Uconnectedwith thefdiaph'rlagm" means I5 in "any Vselected-pr preferred m-anner. I prefer to arrange the r'diaphragm between the two valves so ithe yvalveiI is immediately'below the diaphragm" while rvalve I'I is limmediately above vthe diarfphragm. In the case illustrated vthebody 31 of the'valvei 5 has albonnetf45 threaded with a'boss 46 'on the lower side of the'diaphragm'casing'l and the bodyl 39 Jof'fthevalve I1 'has a'similar' bonnet 41 threaded with'a'b'oss 48'on the upper side of the diaphragm casing. VThis construction yrigidly connectsv'the two valves .II and I1 with theidiaphragm means I1 andmaintains the'twoT *valves in verticalfalignment.

Stern 49 'is `threa'dedwith th'e 'diaphragm hb .13| and'is lockedthereto by'a" nut 5I). -Thestem extends downwardly lthrough' a f `sealing or packfing'means'5I in the'boss'M'and4 extends into the valve I6. -Stem V52u15 threaded with the 'upper' end of the diaphragm hub' 3 I and iis' locked Awith The -.sten1""52 extends `through aipacking orssealingfmeansk 54 in the boss -148-and projects' up intotheyalve I1.

V Ltank falls gto' the bottom-elif .thei tank-:andstheegas rises fromthe liquidwandfnccupiesitha upper iper- Y f charging' through thelfnpple` 105 stri-kes i'thelibaie a heavy fanshaped'spray or :stream whichstrikes fleasethe gas.

This incneasestthe'ratebf-.the s'eparating action of the apparatus. f

Assuming that valve v`I I5l isnclo'sed sand-valve I1 =is'open, gas is Y. freel to discharge! from lineiIS 'cinto l line 6 I vbut-:the foil .orvliquidz isl .retaineddn -the'vtank I0. The weight of thei diaphragm '29, Vdiaphragm `discs 2, the valve'a'stems 49 fiand'ieBZ andithe valve-heads 55 and f5.1,and1the headipressure off the liquid on the valve Lhead 555, 'actto .I'Lopen until thev liquid,headf'actingionithefdia- I phragm- 29 overba-lancesithes'eiforc'es. The-'downofthe assembly or .infthe 'lstrength o'f @any fspning vthat may be used willLvalysthetheigh-tfofathe.nor- .fmal lliquid L. Such variationsor; adjustmentswpf Vlevel -L rises and thefheadipressureorrrhydrostatic .i .pressure Y.of thel column of liquid iin the `ftanlpfi Il vvincreases. This i pressure is .communicated to-the r.under side of f diaphragmwZQ :through line AI v2- .and

:the line S33 .and-to `the upper .side -of `.the valve yli. V-When the hydr'ostaticcpre'ssurecreated by the column-of liquid in-vthe j'tank lilreachesla given value` ity overcomes zoroverbalances' the gravityof the idi-aphragmcassembly, lstems'ff4 9 .z and Y 52--and `headsl55 and d58, -thef ,headA pressure :on

.the valve- I6l (whichisstheweightfof-'the lliquid plus the gaspressurevon :theliquid in the tank) andthe gasmpressure Von fthe--A upper fside of the diaphragm. When thiswoccurs 'the :liquid pressure moves the diaphragm-29 `up andfthein'ter- 'connected valveheads-andustemassemblies also move up, .bringing Aheads -151 4fagainst their seats "44 vto close the valve Ivlandlraisingthe headf'f55 'Upon opening 'of valvev Iii-the oil or liquid discharges .fromline I2 tofline`60-and lwhile/"this 'is occurring therline 'I.3-1-may=remainfclosedor partially closed. This .resultsfin the building --up of gas pressure in 'the upperportion 'of' the ftank "I 0` to act against .the body -ofmli'quidin'the ftank and is Vsuiicient to discharge--thefoilor `Lliquid against any usual fbaclc-fpressure-therefmaybe -in the line-60. -Thuspthevseparator isf operable ffto dlschargef-the fliqui'd or 1foil '.againstlbackfpressures Without employingy outside w-Iiuid pressures lor Whenithe fliquid levelfL falls substantially the .upper side f offvalve' I Strand/f theunder-'- side of didiaphragmpthe"valvestemsfand the valveheaxds,

1the-'pressurer' tending to closeyva-lve d6, and Ithe gas pressuref on 'the-upper sideI ofrtheffdi'aphragm,

overbalance the -upwardfipressure vton* `the :dia-

:- phragm, the -:diaphragm-@movesf=downwardly-and i ImpratiCe-the-edelivery 0f..1;he.f1uid to theitank 175 :the xhead 551cleses-@fontoiits seatvf53awhilecheads f7 ST move awayfrom seats-44. When this occurs the discharge of the oil or liquid is cut off or reduced, while the discharge of the gas under pressure is initiated or increased. Under these circumstances, the liquid again collects in the tank I and the liquid level L rises. The above operations are automatically repeated. It is to be understood that in actual yoperation the level controller may serve to maintain the liquid level L Within a desired range in the tank throughout an extended period of time and regardless of uctuations in the flow or mixture delivered by pipe Il.

From the foregoing description it will be apparent that the action of the valves, for instance the opening of valve I6 and closing of valve I'I, is governed mainly by a combination of two principal factors, namely, the Weight tending to normally close valve I6 and open valve I'I, and the head pressures acting on the diaphragm and valve I6. It will be apparent that the weight factor remains constant and therefore the point at which the valve I6 opens occurs when the liquid level in the tank II) reaches a certain point or height in the tank relative to the position of the control unit at the exterior of the tank. In accordance Vwith my present invention the means I8 is provided for effecting adjusting so that the apparatus can be readily set or adjusted to cause valve I6 to open when the liquid level L reaches any desired point in the tank ID.

The means I8 provides, generally, for varying the vertical relationship of the level control unit and the tank III. Since the tank IIJ is a large bulky unit while the level control comprising the valves and the diaphragm is a relatively small unit it is advantageous, in practice, to provide for movement of the control unit relative to the tank.

The means I8 contemplates, broadly, vertical adjustment of the level control relative to the tank I0. This movement or adjustment may, in practice, be accomplished through various mechanical arrangements. In the construction illustrated the means I8 is in the form of slip joints provided in the lines I2 and I3 and in discharge lines G0 and 6I, where they are provided to receive iiow from the apparatus.

To provide for the adjusting means the pipes I2 and I3 have parallel sections A and B, respectively, preferably vertically disposed, as shown in the drawings. A slip joint 62 is provided in section A of pipe I2 While a slip joint 63 is provided in section B of pipe I3.

The slip joints may be of any suitable construction. For instance, as shown in the drawings, they may involve telescoping parts provided with packing means 65 that can be tightened to maintain iiuid tight connections. It is to be understood, of course, that the slip joints may be so arranged and proportioned as to give the control unit the desired vertical range of movement.

In the case illustrated in the drawings a discharge pipe 60 is provided to carry liquids or oil from the apparatus while a pipe 6I is provided to carry the gas from the apparatus. When pipes such as 60 and 6I are provided they have sections C and D arranged parallel with each other and with the sections A and B of pipes I2 and I3, respectively. In order to allow for free movement or adjustment of the level control slip joints 66 and 61 similar to the slip joints 62 and 63 are provided in the pipe sections C and D, respectively, as clearly shown in Fig. 1.

With the construction hereinabove described the packing 'means of the several slip joints may be tightened to not only make the joints tight but also to create friction so that the liquid level control unit comprising the valves and diaphragm remains in a xed or set position. When it is desired to vary the level of the liquid at which the valve I6 opens the packing means of the several slip joints can be loosened, whereupon the level control unit can be bodily moved either up or down. It is to be noted that the pipe connections 33 and 35 are so related to the slip joints 62 and 63, that is, are connected into the pipes I2 and I3, by the slip joints and the valves so that they are not disturbed by adjustment of the level control unit.

It is important to note that a relatively small rise in the liquid level L will bring about complete opening of the valve I6. I prefer to use relatively small valves I6 and I'I to obtain maximum valve movement in relation to the liquid level change. For example, a liquid level rise of only 3A; of an inch will result in full opening movement in a one inch liquid discharge valve I6. As a result of this the valve head 55 of the valve I6 is moved a substantial distance away from its seat A3 upon only minor changes in the liquid level L. Accordingly, the valve head 55 does not remain only cracked or in close proximity to its seat 43 while the liquid level is rising. The ratio between the liquid level change and the valve movement is such that there is no tendency for the valve head 55 to assume a position where it is in close proximity to its seat 43, in which latter positions the fluid would increase in velocity as it ows past the valve and the solid matter carried by the iiuid would tend to cut out the valve head 55 and seat 43. In the apparatus of the invention a relatively small increase in the liquid in the tank I0 produces substantial opening movement of the valve head 55 providing ample openings for the discharge of the liquid and reducing to a minimum the erosive action of the solid matter carried by the discharging fluid. In this case it should be observed that the diaphragm 29 of large diameter multiplies the eiective liquid head or pressure which opens the valve I6 and it should be further observed that the coupled valves I6 and I 'Lare simultaneously urged to one position by the gravity of their connected stems and heads and gravity of the diaphragm assembly and are simultaneously urged to the other position by the liquid pressure acting on the under side of the diaphragm 29. The liquid pressure acting on the under side of the diaphragm 29 is opposed by the Weight of the diaphragm assembly and the valve stem and head assemblies, the head pressure on valve I6 and the gas pressure on the diaphragm.

The gas pressure acting on the liquid in the tank I'Il to increase the head pressure and on the upper side of the diaphragm 29 balance one another.

It is importantV to note that the diaphragm 29 which serves to control the two valves I6 and I1 is entirely unaifected by back pressures in the discharge lines 6!) and 6I. As above described, the back pressures in the lines do not move the movable elements of the valves. The diaphragm 29 operates in response to the actual pressure conditions existing within the tank I0 and is Wholly unaffected by back pressures in the lines 69 and 6I and it controls the valves I6 and I'I with great accuracy or precision to maintain the required condition in the tank I9 ,at all times. The operation is entirely automatic and is not subject to adjustment or regulation except for the general adjustment above described. The apparatus is such that there is no possibility of incorrect adjustment-.on the part of the operators. There no exposedlinkage and' there arene moving-parts- Within theitankwlll. i

Having described' only a typical preferred form.

andapplicationV of'my invention, 11do not wishtobe4` limited-for restricted' t .the .speciiicv details herein set forth,"but"wish to reserveto mysel-ffany variations or. modications".y that, may ap'pea-rk to; tho-seiskilled in the art or fallwithinthe Scope f;A

ed in the gas outlet from a separator, an oil control valve adapted to be incorporated in the oil outlet from the separator, means directly connecting said valves whereby when the gas valve opens the oil valve will correspondingly close and vice-versa, and pressure responsive means subjected on opposite sides to the pressures in the gas outlet and oil outlet respectively and operatively connected to said valves to open and close said valves in accordance with the dilerential in pressure elective thereon.

2. A control means for oil and gas separators comprising in combination a substantially balanced gas control valve adapted to be incorporated in the gas outlet from a separator, an oil control valve adapted to be incorporated in the oil outlet from the separator, means directly connecting said valves whereby when the gas valve opens the oil valve will correspondingly close and vice-versa, and pressure responsive means subjected on opposite sides to the pressures in the gas outlet and oil outlet respectively and operatively connected to said valves to open and close said valves in accordance with the dilerential in pressures eective thereon, said Valves being biased into a position wherein the gas valve is open and the oil valve is closed.

3. A control means for oil and gas separators comprising in combination a substantially balanced gas control valve adapted to be incorporated in the gas outlet from a separator, an oil control valve adapted to be incorporated in the oil outlet from the separator, means directly connecting said valves whereby when the gas valve opens the oil valve will correspondingly close and vice-versa, and. a housed diaphragm between said valves exposed on that side facing the gas control valve to pressure in the gas outlet from the separator and exposed on that side facing the oil control valve to pressure in the oil outlet from the separator whereby the differential in pres'- sures in said outlets is effective to open and close said valves respectively.

4. A control means for oil and gas separators comprising in combination a substantially balanced gas control valve adapted to be incorpo rated in the gas outlet from a separator, an oil control valve adapted to be incorporated in the oil outlet from the separator, means directly connecting said valves whereby when the gas valve opens the oil valve will correspondingly close and vice-versa, and a housed diaphragm between said valves exposed on that side facing the gas control valve to pressure in the gas outlet from the separator and exposed on that side facing the oil control valve to pressure in the oil outlet from the separator whereby the differential in pressures in said outlets is eifective to open and close said valves respectively, said valves being biased into a position wherein the gas valve is open and the oil valve is closed.

valve adapted tovbez. incorporated in the gas outlet from the separator, an oil control valve adapt- 'ed to be incorporated inthe oil@ outlet from the separator, a diaphragm housing between ythe valves, a diaphragm therein, means rigidly con.

necting said valves` through the -diaphragm whereby when-the-- gas valveisopened the oil yvalve is. correspondingly closed and vice-versa;

means conneotingthe gas outlet between the separator and the gas control valve to that side of the diaphragm housing most adjacent the gas control valve, and means connecting the oil outlet between the separator and the oil control Valve with that side of the diaphragm housing most adjacent the oil control valve whereby the diaphragm is caused to actuate said valves in accordance with the differential in pressures effective thereon.

6. A control means for oil and gas separators comprising a substantially balanced gas control valve adapted to be incorporated in the gas outlet from the separator, an oil control valve adapted to be incorporated in the oil outlet from the separator, a diaphragm housing between the valves, a diaphragm therein, means rigidly connecting said valves through the diaphragm whereby when the gas valve is opened the oil valve is correspondingly closed and vice-versa, means connecting the gas outlet between the separator and the gas control valve to that side of the diaphragm housing most adjacent the gas control valve, and means connecting the oil outlet between the separator and the oil control valve with that side of the diaphragm housing most adjacent the oil control valve whereby thediaphragm is caused to actuate said valves in accordance with the differential in pressures eiective thereon, said valves being biased into a position wherein the gas valve is opened and the oil valve is closed.

7. A floatless oil and gas separator comprising a, tank into which a mixed oil and gas influent may be discharged, an oil outlet leading from the tank, a gas outlet leading from the tank, a substantially balanced valve controlling the gas outlet and located externally of the tank, a poppet type valve controlling the oil outlet and located externally of the tank, said valves being rigidly connected for operation in unison whereby opening of the gas outlet will correspondingly close the oil outlet and vice versa, and a diaphragm arranged between the valves and externally of the tank exposed on that side facing the gas valve to pressure in the gas outlet and exposed on the opposite side to pressure in the oil outlet, said valves being biased to close the oil outlet and open the gas outlet when pressures on opposite sides of the diaphragm are equal.

8. A unitary control for use with a liquid and gas separator having a separator chamber for receiving a liquid-gas mixture and in which are formed gas-containing and liquid-containing portions of the mixture comprising a normally open valve for controlling ow from the gas-contain- Ving portion of the chamber, a normally closed valve for controlling flow from the liquid-containing portion of the chamber, housing structures for said valves, diaphragm means having a housing structure assembled with said valve housing structures, and a diaphragm connected to move said valves simultaneously to open one and close the other, and conduit `connections to said diaphragm means to conduct the fluid pressures in 1 1 said gas and liquid-containing portions to said Number diaphragm means on opposite sdes'of said dia- 548,458 phragm. 1,378,689 RICHARD A. WERTS. 1,428,375 5 1,620,096 REFERENCES CITED 1,691,350 The following references are of record in the 1,941,030 le of this patent: 1,993,790 UNITED STATES PATENTS 2'145114 10 2,167,160 Number Name Date 2,313,797

428,399 Moore May 20, 1890 12 Name Date Reynolds Oct. 22, 1895 Larson May 17, 1921 Humphreys Sept. 5, 1922 Harris Mar. 8, 1927 Harris Nov. 13, 1928 Williams Dec. 26, 1933 Kinsella. Mar. 12, 1935 Gibbs Jan. 24, 1939 Raymond July 25, 1939 Bailey Mar. 16, 1943 

